Root - Root effect causes the victim to be locked in place and unable to move. A root effect differs from a stun effect in that the target is still able to use their Combat Arts or melee/ranged attacks, but cannot move from its location as long as the effect is active. Root duration is not a constant value and depends on CA's level and modifications.

Secondary Damage Effects have a chance to occur when an enemy is hit by a weapon or Combat Art. Burn, Poison and Open wounds inflict a percent of the damage that caused the effect over a time period of 5 seconds (the actual value for effect duration is about 500 frames, which could have been interpreted as 5 seconds, but the game applies damage once a second; so in practice the effect deals damage over five seconds in five pulses).

If the effect is caused by a Critical Hit, then the damage inflicted by that effect also increases by 20%. If a Secondary Damage Effect was caused by a hit with failed Spell Resistance/Spell Intensity check, this effect's damage is likewise decreased by 30%. Several different (not similar!) effects stack, so an enemy can suffer from several effects at the same time. However, only one graphical effect is displayed at a time.

The fundamental difference between Damage over Time, caused by Spell Damage Based Combat Arts and the periodic damage caused by Secondary Damage Effects (open wounds, burn, poison) is the latter's dependence on flat damage. The periodic damage of a Secondary Damage Effect is directly proportional to the inflicted damage that caused the effect. Periodic damage caused by Secondary Damage Effect depends on how much damage the character has received: for example, if character's armor absorbs 75% incoming damage, periodic damage caused by Secondary Damage Effect will also inflict 75% less damage.

Calculations

Damage of Secondary Damage Effect caused by CloseCombat\Ranged, Weapon Damage Based CAs and Spell Damage Based CAs is calculated by the formula:

vs monsters

When triggered, effect will cause periodic elemental damage. The enemy will sustain five hits (each hit 1 second after the other), total damage of which is 20% of the initial blow's elemental damage composition. For example, if the hit dealt 100 damage of pure poison damage and triggered Poison, the enemy would take five hits of 20 poison damage each (100 damage over time in total). This percentage can be modified by Damage Lore skill mastery.

As can be seen from the formula, periodic damage caused by DME depends on how much damage has received the character: for example, if character's armor absorbs 75% incoming damage, periodic damage caused by DME will also inflict 75% less damage.

I would like to emphasize: Damage Mitigation protects from DME twice - first DM reduces incoming flat damage (periodic damage depends on how much damage has received the character), secondly DM reduces damage from incoming periodic damage (open wounds, burn, poison). For example, 50% Damage Mitigation reduces damage over time at 50%, and then another 50 %, a total of 75% mitigation.

If the defender's willpower value is too much, the damage dealt by Secondary Damage Effects would be noticeably reduced. It works only against Spell Damage Based Combat Arts that deal flat damage and have a chance for secondary effects. If an attack inflicts such effect (for example, Burn effect from a Dragon's fireball or Poison from Kobold Shaman's projectiles) then the duration of effect on highly resistant character would be reduced. Therefore the effect deals only some % of its original damage.

Defender's Willpower attribute does not affect:

Pure Damage over Time, caused by Spell Damage Based CAs (poison attacks of Undead and Toxic Elementals for example)

Combat Arts that deal mixed damage - both flat damage and DoT (not to be confused with CAs that deal flat damage with a chance of detrimental effect). Examples of such CAs are High Elf's Frost Flare, Ice Elementals' ice projectiles and Spit CA of the Weaving Spiders. Willpower affects Secondary Damage Effects, caused by flat damage, but ignores build-in Damage over Time.

The Detrimental magic effects -x% modifier reduces the duration of such effects as well as damage dealt by them (damage is reduced proportionally to the time). If several bonuses of this kind are equipped at the same time, their percentage does not sum up, final sum can be calculated using the following formula:

Therefore the character can never achieve 100% reduction of detrimental effects.

Some Detrimental Magic Effects (Burn, Poison and Open Wounds) are classified as DoT and therefore affected by Damage Mitigation +x% and DoT -x% modifiers as well as by Mastery of Spell Resistance skill.

Many monsters have Combat Arts of this type (they are classified as DoT and Detrimental Effects at the same time). Such CAs do not deal flat damage and therefore are not affected by armor - they only inflict DoT over 5 seconds after attack (Poison attack of Undead and Toxic Elementals for example).

Notes

For one minimal in-game time (1 frame) no more than one hit (of flat damage) on the target can cause a Secondary Damage Effect, and from this hit a chance to cause an efect is calculated. This means that even a million Glacial Thorns, simultaneously inflicting damage, have the same chance to cause Freeze as a single Glacial Thorn.

Reflected damage can not cause Detrimental Magic effects.

There are 2 defenсes against De-buffs: "detrimental Magic Effects -x%" modifier and "Spell Resistance" skill mastery (which also gives the character "Detrimental Magic Effects -x%" modifier, depending on skill level). At first theese defenсes reduce debuff duration, secondly they reduce the power of effect. For example, 75 hard points in SR skill and "Detrimental Magic Effects -33%" modifier in total give the character 65+11* = 76% reduction of debuff power and duration. Defenсes are calculated layerwise (have diminishing returns) , so immunity can not be achieved.